10 THE THEORY OF EVOLUTION 



manner of life, are changed, the characters of stature, 

 form, proportion of parts, colour, consistency, dura- 

 tion, agility and industry in animals are proportion- 

 ally changed. 



"They could see that in animals the more frequent 

 and sustained use of any organ gradually strengthens 

 and develops that organ, enlarges it and gives it a 

 power in proportion to the duration of that use; 

 while constant disuse of such an organ insensibly 

 weakens it, deteriorates it, progressively diminishes 

 its capacities, tends to destroy it. 



'' Finally, they could note that everything which 

 nature causes individuals to acquire or to lose through 

 the sustained influence of circumstances to which the 

 race has long been exposed, she transmits by genera- 

 tion to the new individuals which spring from them. 

 These truths are constant and cannot be mistaken 

 save by those who have never observed and followed 

 nature in her operations." 



Lamarck, as already noted, had but few disciples 

 in his own or immediately succeeding times, largely 

 because of the opposition of Cuvier, who wielded a 

 despotic authority over scientific opinion in France. 

 In Germany also the evolutionary theory fell into 

 complete discredit, but for another reason; in that 

 country the theory had been advocated chiefly by 

 the so-called :< Natural Philosophers," whose wild 

 and fantastic speculations finally disgusted sober- 

 minded men and turned their labors into more ob- 



1 Alfred Giard: Controverses Transformistes, Paris, 1904, pp. 13, 14. 



